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<font size="-1">Hello,<br>
<br>
You will find here (</font><font size="-1"><font size="-1"><a class="moz-txt-link-freetext" href="https://www.dropbox.com/s/ayo93hi4togpc9m/noGom.lp?dl=0">https://www.dropbox.com/s/ayo93hi4togpc9m/noGom.lp?dl=0</a></font>)
a constraint file for which cbc founds a solution when Gomory cuts
are removed or for specific cutlength values.<br>
<br>
In other words, the following command leads to an infeasible
problem:<br>
<i>/soft/cbc-trunk-2149/bin/cbc noGom.lp branch printingOptions
normal solution noGom.sol</i><br>
<br>
and with the following commands, cbc claims that there is a
solution:<br>
</font><font size="-1"><font size="-1"><i>/soft/cbc-trunk-2149/bin/cbc
noGom.lp gomory off branch printingOptions normal solution
noGom.sol</i></font><br>
</font><font size="-1"><font size="-1"><i>/soft/cbc-trunk-2149/bin/cbc
noGom.lp cutlength xx branch printingOptions normal solution
noGom.sol</i></font> (with xx equal to -1, 0, 10, 20... and
different from 30...)<br>
<br>
Since our problems are dynamically generated, it is very painful
to try to solve them with different options, hoping that the right
set is in the list.<br>
<br>
</font><font size="-1">So, is there a way to find this set of
options.<br>
Or could you explain what are the rows that are difficult for cbc.<br>
And, does the change of the continuous variables into integer
variables help? (for our problems, it makes sense).<br>
<br>
Thanks and regards<br>
<br>
Yves<br>
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